Circuit used in digitizing analog video from an image pixel array

Abstract

Disclosed herein is a camera system and camera controller having a modularized design. Camera control functions within the controller are distributed among a number of modules, each module performing a component task of controlling a camera. Individual modules can perform tasks such as generating clock signals, digitizing an analog video signal, and providing multiplexed digital video output. Modules communicate with each other over a common bus sufficient to carry the signals necessary to control the camera. The system implements a RAM-based digital sequencer that provides the capability of loading bit patterns into memory and using these patterns to generate waveforms for clocking a CCD. Clock and readout sequences can be composed in a high level language, compiled and uploaded into the controller. Adjustable clamp and sample signal delays used in digitizing an analog video signal provide the capability to optimize the performance of the system in a given application.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a divisional application from U.S. application Ser. No. 10 / 457,052, filed on Jun. 6, 2003, which claims priority from Provisional Application No. 60 / 387,316, filed Jun. 7, 2002. Both of these applications are incorporated herein by reference in their entirety.FIELD OF THE INVENTION[0002]This invention relates generally to charge coupled devices (CCDs), MOS, and other pixel sensor arrays, cameras, controllers, imaging systems, and methods of controlling and operating the same. The invention is directed to a controller and camera system having a modularized architecture making it extensible to all known types of CCDs and other pixel sensor arrays. The present invention is particularly well suited for use in scientific imaging applications such as adaptive optics, wavefront sensing, interferometry, fringe tracking, and neuroscience research. The small form factor with remote head of the present invention also makes the sy...

AI Technical Summary

Benefits of technology

[0014]The command module can include an external interface to allow an external device to select a program to be run by the command module. The external interface can also allow the camera controller to be synchronized with other devices. Additional output signals such as start-of-integration and start-of-sequence signals can be provided on the external interface to allow for more robust external synchronization and control.

[0015]Input modules of the present invention can use correlated double sampling in digitizing an analog video signal from a camera head. The input modules can additionally include clamp and sample delay circuits to allow for optimization of camera performance. These circuits can allow for the delay of clamp and sample signals in one quarter nanosecond increments. Furthermore, a high speed shunt can be included that allows the low pass filters of the input module to be bypassed in order to speed the relaxation of a CCD output from a reset pulse. The high speed shunt can comprise an operational amplifier having a high speed enable.

[0016]The clock driver modules of the present invention comprise adjustable voltage regulators which can be adjusted to match the clock outputs of the camera controller to the input requirements of a CCD. A first voltage level can be set and then a voltage span can be set. By setting the clock driver voltage levels in this manner, the likelihood of accidentally damaging a CCD can be reduced.

Problems solved by technology

The storage pixels, however, take up space within the image and they therefore result in the disadvantage of the image pixels not being contiguous.

Many of the technologies used in prior art cameras are becoming obsolete.

One of the major disadvantages of the prior art is the difficulty in achieving the very highest performance in terms of small form factor, high frame rate and low readnoise with a variety of different CCDs due to the diversity of CCD input and output requirements.

Images